The present disclosure relates to a surgical instrument and method for performing anastomosis of tubular body structures, and more particularly to an instrument for joining tubular tissues, for example, during gastrointestinal procedures.
Surgical stapling devices for applying an annular array of staples or fasteners to tissue are well known in the art. For example, surgical stapling devices for applying an annular array of staples, as well as devices for completing a surgical anastomosis through the provision of anastomosis rings, are well known in gastric and esophageal surgery, for example in classic or modified gastric reconstruction typically formed in an end to end, end to side, or side to side manner.
These devices generally include a circular array of fasteners such as staples, anastomosis rings, and the like, while the anvil member includes means for completing the circular anastomosis, typically an array of bucket members that cinch the staples after the staples are expelled from the fastener assembly, or may include a locking member for the anastomosis ring.
In use, the anvil is positioned within the lumen of an organ such as the stomach, esophagus, or intestine and the tissue is pulled about and around the anvil member and tied off, e.g., by a purse string suture, ring mechanism or the like. The fastener assembly is then positioned within the opposite end of the lumen and the tissue is pulled about and around the fastener assembly over the staple array and also tied off. At this point the tissue is positioned between the anvil and the fastener assembly. The anvil is typically slowly retracted (or advanced) to approximate the two tissue halves prior to deformation of the staples usually by virtue of a wing-nut and worm gear assembly which allows a surgeon to methodically advance the anvil towards the staple array to hold the tissue between the anvil and the fastener assembly. Many prior art devices also provide a visual indicator to signal the surgeon when the anvil has reached a firing position adjacent the staple or fastener assembly.
The surgeon then unlocks a safety device deform the staples against the anvil. As the staples or the fasteners are expelled from the fastener assembly, a circular knife typically follows the application of the staples to excise unwanted tissue at the anastomosis site. The instrument is then removed from the lumen of the organ.
The closing mechanisms associated with the prior art stapling or fastening devices typically utilize a complex worm gear arrangement or screw bearing member to approximate the spacing between the anvil and the fastener assembly. As mentioned above, this requires additional manipulation of the instrument by the surgeon during the surgery, e.g., the surgeon must grasp the device with one hand while rotating the knob or wing-like assembly with the other hand. As can be appreciated, moving the anvil member the full distance towards the fastener assembly can be a time consuming process during the surgical procedure. For example, many of the known prior art devices require 15 to 20 full 360xc2x0 rotations of the knob or wing nut assembly to fully close the instrument in order to fire or expel the staples or fasteners into the tissue.
As can be appreciated, it would be advantageous to eliminate many of the above steps for performing the circular anastomosis of these tissue structures to expedite the overall surgical procedure. It would also be extremely advantageous to simplify the overall anastomosis procedure and reduce the level of manual intervention by the surgeon with respect to tying off the tubular ends prior to staple deformation. Moreover, it would be advantageous to provide an instrument which can perform end-to-end anastomosis deep within a tubular structure, e.g., colon, where known prior art devices cannot reach and the surgeon is forced to perform an gastrotomy and then make an incision within the side of the tubular structure to utilize these prior art devices.
A need also exists to develop a device which can be useful for low anterior resection of the colon which has proven difficult with a number of prior art devices. In addition, it would be useful to provide a device where the eversion of the tissue is exterior to the colon which facilitates future repair if needed and reduces the chances of stenosis at the anastomosis site. It would also be helpful to provide an instrument which reduces the amount of healthy tissue removed from the site during the anastomosis.
The present disclosure relates to a surgical instrument for performing an end-to-end anastomosis of first and second luminal structures, such as two portions of the small intestine during an gastrointestinal procedure. The instrument includes a housing having an actuator attached thereto and a selectively removable loading unit attached to a distal end of the housing. The loading unit is dimensioned to support any array of surgical fasteners at a distal end thereof. Upon activation of the actuator, the surgical fasteners simultaneously deform such that a distal end of each of the surgical fasteners secures each end of each luminal structure to complete the end-to-end anastomosis.
In one embodiment, the surgical fasteners include a convexity and a base leg which cooperate after deformation of the surgical fasteners to securely retain the two luminal structures in close abutment with one another. Preferably, the distal ends of the surgical fasteners penetrate at least one of the ends of one of the luminal structures. In another embodiment, the surgical fasteners include a base leg and a proximal portion and the surgical fasteners are supported in the loading unit in an angular manner relative to a longitudinal axis extending through the loading unit. Upon deformation, the base legs of the surgical fasteners deform at an angle relative to the proximal portions of the surgical fasteners.
In yet another embodiment according to the present disclosure, the loading unit is disposable and includes two halves which are pivotable relative to one another. Preferably, the two halves of the loading unit when closed form an elongated aperture for receiving the first luminal structure therethrough. Prior to activation of the actuator, the two halves of the loading unit are pivotally secured relative to one another. Upon actuation, the two halves are unsecured allowing the halves to pivot relative to one another to release the first luminal structure from within the elongated aperture.
In still yet another embodiment, the distal end of the loading unit includes an anvil for retaining the distal ends of the surgical fasteners and for supporting an everted end of the first luminal structure. Preferably, the anvil includes an angled surface which causes the distal end of the surgical fasteners to deform proximally during firing.
In another embodiment, the loading unit includes a series of elongated channels and each of the channels includes a distal end and a proximal end. Each distal end of each channel is radially offset from each proximal end such that the proximal and distal ends of the surgical fasteners are supported in a radially offset manner.
The present invention also relates to a method for creating an end-to-end anastomosis between first and second luminal structures. The method includes the steps of:
providing a surgical instrument which includes: a housing having an actuator; a disposable loading unit removably mounted to the housing, the disposable loading unit being configured to releasably support a plurality of surgical fasteners; and a retractable anvil being movable to simultaneously deform the surgical fasteners;
inserting an end of the first luminal structure into a passage defined within the loading unit;
everting the first luminal structure over the retractable anvil;
inserting a distal end of the disposable loading unit into an end of the second luminal structure such that a distal end of each of the plurality of fasteners and the first luminal structure are sufficiently inserted into the second luminal structure; and
activating the actuator to retract the anvil to simultaneously deform the surgical fasteners and complete the end-to-end anastomosis wherein the resulting eversion is exterior to the luminal structures.